1. Field of the Invention
The present invention relates to a video signal receiver including a display synchronizing signal generation device and control method thereof. More particularly, the present invention relates to a video signal receiver and control method thereof, which prevents twitching and freezing of a screen, even though input and output frame rates do not correspond.
2. Description of the Related Art
An analog video signal receivable at an analog video signal receiver generally includes a CVBS (Composite Video Bust Synchronization), an S-video signal, and a component signal.
The CVBS may be received through a tuner included in the analog video signal receiver or input through a VCR (Video Cassette Recorder) connection terminal.
The S-video signal may be input into the analog video signal receiver through a terminal connectable with an S-VHS (Video Home System), VCR, or a DVD (Digital Versatile Disc) capable of outputting the S-video. The S-video signal comprises a luminance signal Y and a chrominance signal C.
The component signal may be a RGB (Red, Green, and Blue) signal. Alternatively, the component signal may be in a Y/Pb/Pr or a Y/Cb/Cr form. The component signal may be input into the analog video signal receiver through a terminal connected with a device such as a computer.
The analog video signals may have a horizontal frequency and a vertical frequency changed according to peripheral environments. For example, the VCR may have such changes in the horizontal frequency and the vertical frequency in a more severe level by a recording method and a deck velocity.
However, a frequency of a display pixel clock used for the analog video signal receiver is fixed. The display pixel clock outputs the received video signal at a time suitable for a display panel.
Accordingly, the horizontal frequency and the vertical frequency of the video signal displayed at the analog video signal receiver may be variable by a set vertical mode or horizontal mode. The vertical mode may be defined as the total number of lines per frame and the horizontal mode may be defined as the total number of pixels per frame.
The analog video signal receiver has the fixed frequency of the display pixel clock and differences may be created between the input frame rate and the output frame rate when the horizontal frequency and the vertical frequency of the input video signal are varied.
According to the related art, image shortages to the display are complemented by repeating the images when an input frame rate is faster than an output frame rate which causes a screen to twitch.
In the related art, remaining images to be displayed are handled by skipping the images when the input frame is later than the output frame rate which causes the screen to freeze.
Accordingly, there is a need for an improved system and method for providing a video signal receiver to prevent screen twitching and freezing.